1HDT Overheating

[Ghostrider I]

Ok...have a 91 80 series with the 1HDT Turbodiesel. Replaced radiator (aluminium) and water pump 5years ago. A week ago, it was blowing gray exhaust upon idle after a 45 min highway speed drive. Water temp was around 180, oil 200.

Today did same drive, lots more gray exhaust and water temp was 220 oil 220. Coolant overflow tank was bubbling, fired on heat but no heat coming out of vents. It has never in my ownership has overheated, in fact literally ran cool.

Thermostat?

 

[duncanrm]

Are you losing coolant? If so I'd be pressure testing the cooling system, and I suspect it'd be closely followed by the cylinder head coming off.

If you're not losing coolant, I'd be doing a pre-emptive full cooling system rebuild - water pump, thermostat, viscous fan hub, radiator flush, block flush, heater core flush.

 

[Rigpig]

head gasket

 

[Eurasiaoverland]

Despite your confidence to the contrary in your other post, that sounds like a cracked head/leaking head gasket. Coolant is bubbling because combustion gases are getting into the coolant passages, heater does not put out heat because it's full of air. Faulty thermostat would not explain air in the system. Unless there was a major coolant leak, your coolant has gone out of the exhaust pipe. Which is your greyish smoke.

Steel head gaskets don't blow like fibre/bitument gaskets, so unfotunately it's likey to be more than just a gasket. But as per Duncan's post, I would elimiate the simple (cheaper) stuff before removing the head.

 

[Squash]

Check that the rad and overflow are in equilibrium.
If either is low you are losing coolant.
This may take a few days, but tighten all clamps, white spray paint will highlight coolant leaks.
Your overflow should always have some coolant, if this is dry, again a leak.

 

[Skter505]

Get yourself a block tester or find someone who has one. Tests for hydrocarbons in your coolant and gives you a definitive answer on your head gasket in seconds.

 

[sebaguerow]

Same problem here but no gray smoke, change everything in term of cooling, but I think my fan does not spin hard enought! And i have a small leak on the heatear conections, a mechanic said that when just a little air enter the system it would stop working properly, I will fix that and report again, i its does not work its definitly HG failure

 

[VADUS]

Coolant overflow tank was bubbling,

This is a really bad sign. You need to make test for gases in cooling system. Before starting, check if the radiator cap is working properly/closed tightly and no leaking. Just take the radiator hose out of the overflow tank and put it in the transparent bottle (glass) with water. Run fully heated engine with high rpm and observe for the bubbles in water. If there are some - it means, that exhaust comes from the cylinders into a cooling system. The head gasket on this engine is metallic one, so there is nothing to burn out in it. Consider curved plane of cylinder head because of overheating, or worse problem - cracks in the cylinder head. Worst and very rear option - cracks in the cylinder block.

but no heat coming out of vents.

that means you are out of coolant, which is probably out through the cylinders, like guys said above. It usually gives withe smoke (or light grey) with sweet taste.

i its does not work its definitly HG failure

Forget about HG if it is original. Make the same test for bubbles. If there is NO bubbles: check for coolant level, check the fun viscous clutch is working properly, check the both radiators for clearness, especially the gap between them, check the thermostat is opened on time, check the radiator cap for pressure holding.

 

[VADUS]

You need to keep in mind, that 1HD series are very cool and cold engines with direct injection and high volumetric efficiency, UNLIKE 1HZ with its often overheating problems due to the indirect injection into the prechambers inside the head. If any H engine is overheating, then the problem is serious (except for 1HZ) and needs to be found and fixed immediately (also and especially for1HZ). If the cooling system is absolutely working and clear outside and inside, and there are no gases in overflow tank, then consider a problems with injection nozzles and injection timing, which might be too late.